Congratulations to Zhipeng Jiang for the research paper " In-situ Characterization of Over-Lithiation of Organosulfide-Based Lithium Metal Anode " accepted by ACS Appl. Mater. Interfaces.

Abstract

Perlithiated organic sulfides, such as sulfide polyacrylonitrile (SPAN), can form Li2S rich SEI in situ, which is an effective way to protect lithium metal negative electrode (LMA). However, little is known about the mechanism of overlithium and the evolution of the corresponding electrode surface. In this work, we combined a variety of in situ characterization techniques to study the mechanism of SPAN overlithium, including in situ Raman spectroscopy to reveal the changes of SPAN chemical bonds in the process of overlithium, and in situ electrochemical atomic force microscopy visualization of interface evolution during the process of overlithium. The results show that the C-S/S-S bond in SPAN molecules will gradually break during the process of overlithium, leading to the formation of C-Li bond and the decomposition of electrolyte, thus forming a composite interface rich in various inorganic and organic components on the surface. The composite interface has both fast lithium ion transport and excellent mechanical stability. The stability of SPAN based lithium metal negative electrode can be improved significantly. This work not only provides a unique insight into traditional organic sulfur cathode, but also has important guidance for the design of high performance lithium metal cathode.

https://pubs.acs.org/doi/abs/10.1021/acsami.1c09190